First of all, I agree that I preferred when you could change numbers without going onto the Editor page.
Secondly, a sort of roundabout way to get rid of the issue with the wrong numbers being retired would be to provide us the option to unretire numbers. This is obviously not something that happens in real life but I see no reason not to add it to the game in case of accidents/mistakes.
Another thing with regards to numbers that could be cool is a display of all the numbers a player has worn over the course of his career. I'm thinking something like you see on a player's Baseball Reference page (
example) where each number is sort of stylized based on the team's colors.